California Code, Family Code - FAM § 3101

(a) Notwithstanding any other provision of law, the court may grant reasonable visitation to a stepparent, if visitation by the stepparent is determined to be in the best interest of the minor child.

(b) If a protective order, as defined in Section 6218, has been directed to a stepparent to whom visitation may be granted pursuant to this section, the court shall consider whether the best interest of the child requires that any visitation by the stepparent be denied.

(c) Visitation rights may not be ordered under this section that would conflict with a right of custody or visitation of a birth parent who is not a party to the proceeding.

(d) As used in this section: